Hybrid mattress unit

ABSTRACT

An innerspring unit with a plurality of helical coils arranged in at least one array in which the coils are generally aligned in rows, with the coils having generally cylindrical bodies formed by helical turns of the spring with openings in between each of the helical turns. The embodiment may also include a plurality of compressible support members, each of which is secured within at least one of the openings so that each one of the compressible support members is secured within an opening. The compressible support members may be stacked on top of one another. A plurality of innerspring units may be arranged together to form a mattress.

BACKGROUND OF THE INVENTION

A traditional mattress generally has an innerspring unit, enclosed within a mattress cover. Such traditional innerspring mattresses often include a middle layer of spring units of selective variable stiffness, which are arranged in between a top layer and bottom layer of foam, textiles, or other resilient elements.

More recently, memory foam mattresses have become more popular. Memory foam mattresses do not use springs, but instead depend on the ability of the foam to both mold to a person's body shape and return to its original shape once pressure is removed. However, a disadvantage to memory foam mattresses is that they may not provide as much support as an innerspring mattress in that, overtime, the foam loses its ability to return to its original shape and a user thereby sinks further into the foam.

SUMMARY OF THE INVENTION

The present invention relates to a hybrid mattress unit that combines the characteristics of a traditional innerspring mattress and memory foam mattresses.

In one embodiment, the invention relates to a mattress having a top and a bottom and a plurality of springs, each with a longitudinal axis, such that each of the springs has a number of coils, so that the space between two coils defines an opening, and the springs arranged in a direction such that their longitudinal axes are perpendicular to the top and bottom of the mattress. This embodiment also includes a plurality of foam strips, each of which having a thickness, such that the strips are arranged with the plurality of springs so that at least one side of each strip is secured within an opening defined by two coils of a spring.

In another embodiment, the invention includes an innerspring unit with a plurality of springs arranged in at least one row whereby the body of each spring is generally cylindrical and each spring has at least two coils and a longitudinal axis. This embodiment may also include a plurality of resilient elements each having a height dimension, a width dimension, and a length dimension, arranged such that the length dimension is secured in between two coils of at least one spring. The height dimension fits between the two coils of the spring.

In yet another embodiment, the invention includes an innerspring unit with a plurality of helical coils arranged in at least one array in which the coils are generally aligned in rows, with the coils having generally cylindrical bodies formed by helical turns of the spring with openings in between each of the helical turns. The embodiment may also include a plurality of compressible support members, each of which is secured within at least one of the openings so that each one of the compressible support members is secured within an opening. The compressible support members may be stacked on top of one another.

The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL DRAWINGS

FIG. 1 is an isometric view of a portion of the mattress.

FIG. 2 is an enlarged isometric view of a first embodiment of an innerspring unit.

FIG. 3 is an enlarged isometric view of the embodiment shown in FIG. 2, with one spring disengaged from the foam strips.

FIG. 4 is an isometric view of the embodiment shown in FIG. 3, with both springs engaged with the foam strips.

FIG. 5 is an enlarged side view of one spring engaged with the foam strips as shown in FIG. 4.

FIG. 6 is an enlarged side view of a second embodiment of the innerspring unit.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a portion of a mattress unit 10 with a plurality of innerspring units 12 enclosed within a mattress cover 14.

In the embodiment of a mattress shown in FIG. 1, the mattress 10 has a top 16 and a bottom 18, such that the top 16 of the mattress is the portion that a person lays on, and the bottom is adjacent to the floor or other mattress-supporting surface, such as a box spring. The plane defined by the top 16 of the mattress may be parallel to the plane defined by the bottom 18 of the mattress.

The mattress 10 shown in FIG. 1 includes several innerspring units 12, the structure of such innerspring units 12 is shown in more detail in FIGS. 2-6. A full innerspring unit 12 is shown in FIG. 2. In one embodiment of the invention, an innerspring unit 12 is made of a plurality of resilient elements 20. The resilient elements 20 may be made of a form of compressible support members such as memory foam strips, polyurethane, polyester fibers, polymer fibers or other material which may be suitable for a mattress. A selected number of innerspring units 12 can be arranged together to form a mattress 10.

Each resilient element 20 may have a height dimension 22, or a thickness, a width dimension 24, and a length dimension 26. The height 22, width 24, and length 26 dimensions depend upon the desired characteristics of the resulting mattress unit 10. For example, in one embodiment, the length dimension 26 may dictate the width of the mattress. However, in another embodiment, the length dimension 26 may dictate the length of the mattress 10, depending on the orientation of the innerspring units 12 with respect to the desired mattress size. The height dimension 22 may be selected based the structural characteristics of the springs 28 used to fit within a given opening 38 defined by a spring 28, as will be described in more detail. In one embodiment of the present invention, the height dimension ranges from 1 inch to 1.5 inches.

Multiple resilient elements 20 may be stacked, as shown in FIGS. 2-6, and engaged or secured in such a stack with the use of one or more springs 28. One stack secured by one or more springs 28 is hereby referred to as an innerspring unit 12. A disengaged spring 28 is shown in FIG. 3. A spring 28 may be made of a metal wire such as steel, and may be helical such that it is spiral shaped with a longitudinal axis 30 at its radial center as viewable in FIG. 3. The longitudinal axes 30 may be generally normal to the plane of the top 16 and bottom 18 of the mattress. In some embodiments, the spring 28 also has a cylindrical shape with a consistent diameter 40. In other embodiments, the spring 28 may have a variable diameter such that the coils vary in size within a spring 28 (not shown). Turns of the helical spring 28 define openings 38 in between each turn of the spring 28. A spring 28 may also have at least two coils 32 such that a resilient element 20 may be secured in the opening defined between two coils 32 of the spring 28. FIG. 3 generally represents how a spring 28 may be used to secure a stack of resilient elements 20 by inserting one resilient element 20 in between two coils 32, as represented by arrow 34.

One or more springs 28 may be used to secure a plurality of resilient elements 20 stacked on top of one another. For example, the embodiment shown in FIG. 2 uses six springs to secure a stack of five resilient elements. The mechanical characteristics of a spring 28 such as a compression spring is utilized to both secure the resilient elements 20 in place and to store mechanical energy. When such a spring is stretched, the force it exerts to return to its original position is proportional to the length that it is stretched. Therefore, by stretching a spring 28 and inserting one or more resilient elements, the elastic characteristic of the compression spring 28 would compress the elements between its coils 32, thereby holding the resilient element(s) 20 in place.

Springs 28 may be secured on just one side of a stack of resilient elements 20, as shown in FIGS. 2 and 3. Springs 28 may also be secured on two sides of a stack of resilient elements 20 as shown in FIG. 4. However, springs 28 may be secured with resilient elements 20 in other manners and on other sides of the stacks other than the arrangements shown in the present embodiments. Such coils may also be anchored to a mattress frame (not shown).

Characteristics of the resilient elements 20 may be selected based on user preference. For instance, in one embodiment shown in FIG. 5, each resilient element has the same height dimension 22. In the embodiment shown in FIG. 6, the height dimension 22 of the resilient elements 20 is greater on the bottom of the stack and progressively decreases toward the top of the stack. With such a configuration of a stack of resilient elements 20, if pressure is applied to the top of the stack, for instance if a person lays down on a mattress, the person will sink further into the stack, thereby feeling a softer mattress, before the resistance of the spring(s) 28 are felt. This result is due to the spring coils being stretched further at the bottom of the stack due to the resilient element 20 with a greater height dimension 22. In one embodiment, memory foam is used as a resilient element 20, such that once applied pressure is removed, the foam expands vertically to its original position.

The stippled lines 36 in FIGS. 5 and 6 shows the portions of the spring 28 which are hidden from view, wherein the springs elastically deform the resilient elements 20 in securing such elements. The resilient elements 20 may also varied based density of foam type. The density of memory foam can affect the durability and the resistance to pressure of the mattress. In one embodiment of the invention, the density of the memory foam can be from 18 to 55 IFD (indention force deflection). Such density characteristics can hereby be varied among a stack of resilient elements 20.

By combining springs 28 with such resilient elements 20 like memory foam, a mattress 10 incorporates the ability of memory foam to distribute pressure with the resiliency and spring qualities of innerspring mattresses. The engagement of the springs 28 with the resilient elements 20 to form innerspring units 12 also decreases potential noise caused by the springs 28.

The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow. 

What is claimed is:
 1. A mattress having a top and bottom, comprising: a plurality of springs with longitudinal axes, and each spring within said plurality exhibiting a number of coils, such that a space in between two coils defines an opening, said springs arranged in a direction such that said longitudinal axes are perpendicular to said top and said bottom of said mattress; a plurality of foam strips, each strip having two elongate sides and a thickness, said strips arranged such that at least one side of each strip is secured within an opening defined by two coils of a spring.
 2. The mattress of claim 1 wherein said plurality of foam strips includes at least two different thicknesses.
 3. The mattress of claim 1 wherein said thickness is between 1 inch and 1.5 inches.
 4. The mattress of claim 1 wherein said plurality of foam strips includes foam strips of at least two different densities.
 5. The mattress of claim 4 wherein the density is between 18 and 55 IFD.
 6. An innerspring unit for a mattress, comprising: a plurality of springs arranged in a row, the body of each spring being generally cylindrical, having at least two coils, and having a longitudinal axis; a plurality of resilient elements each having a height dimension, a width dimension, and a length dimension, arranged such that the length dimension of said plurality of resilient elements is secured between two coils of said springs, whereby the height dimension fits between said two coils.
 7. The innerspring unit of claim 6, wherein a plurality of units are arranged to form a mattress.
 8. The innerspring unit of claim 6, wherein a resilient element is secured within each coil of each spring, thereby forming a stack of resilient elements secured in such a stack by said coil.
 9. The innerspring unit of claim 8, wherein said stack generally has a top side and a bottom side, and a resilient element adjacent the top side has a shorter height dimension than a resilient element adjacent the bottom of side of the stack.
 10. The innerspring unit of claim 6 wherein said height dimension is between 1 inch and 1.5 inches.
 11. The innerspring unit of claim 6 wherein each of said resilient elements has a density between 18 and 55 IFD.
 12. The innerspring unit of claim 6 wherein said plurality of resilient elements includes at least two different height dimensions.
 13. The mattress innerspring of claim 12 wherein said height dimension is between 1 inch and 1.5 inches.
 14. A mattress innerspring comprising: a plurality of helical coils arranged in an array in which the coils are generally aligned in rows, each of the coils having a generally cylindrical coil body formed by helical turns of the spring with openings between each of the helical turns, having a longitudinal axis; a plurality of compressible support members, each of which is secured within at least one of said openings, said compressible support members are stacked in the direction of said longitudinal axis; and wherein said plurality of the coils and the compressible support members are arranged together to accommodate a user-selected seize of a mattress.
 15. The mattress innerspring of claim 14 wherein said plurality of compressible support members includes at least two different thicknesses.
 16. The mattress innerspring of claim 15 wherein said thickness is between 1 inch and 1.5 inches.
 17. The mattress innerspring of claim 14 wherein said plurality of compressible support members includes compressible support members of at least two different densities.
 18. The mattress innerspring of claim 17 wherein each of said compressible support members has a density between 18 and 55 IFD.
 19. The mattress innerspring of claim 14, wherein said stack of compressible support members generally has a top side and a bottom side, and a compressible support member adjacent the top side has a shorter height dimension than a compressible support member adjacent the bottom of side of the stack. 